Stapling machine



A. E. CAIRATTI STAPLING MACHINE April 7, 1970 3 Sheets-Sheet 1 Filed April 24, 1968 FIG! mMhmin-n 111111111111- A. E. CAIRATTI STAPLING MACHINE April 7, 1970 3 Sheets-Sheet 2 Filed April 24, 1968 FIG.2

Imam/r02 04 779040 A. (w/24717 B) a 2 FIG.4

April 7, 1970 A. E. CAIRATTI 3,504,839

STAPLING MACHINE Filed April 24, 1968 I 3 Sheets-Sheet s llll I III 3,504,839 STAPLING MACHINE Anthony E. 'Cairatti, Herrin, Ill., assignor to Werner Schafroth, Herrin, Ill. Filed Apr. 24, 1968, Ser. No. 723,692 Int. Cl. B25c /04, 7/00; B27f 7/10 US. Cl. 227108 9 Claims ABSTRACT OF THE DISCLOSURE This invention relates in general to stapling machines and means for feeding cut wires to the staple forming and driving mechanism. In particular, this invention relates to a stapling machine of the retractable anvil type having an improved feed and forming block arrangement.

This invention represents a practical improvement over the stapling machines and magazines heretofore used, such as shown in Schafroth Patent No. 2,897,502 dated Aug. 4, 1959, Schafroth et al. Patent No. 3,279,673 dated Oct. 18, 1966, and other prior Schafroth stapling machine patents.

In the past, it has been common practice to drive preformed staples in clips with retractable anvil stapling machines. With high speed production requiring the closing of many cartons in each unit of time, the magazines required frequent reloading or had to be of a very long length. Even long magazines required frequent reloading.

In the past, stapling machines have been made to utilize cut wires which can be rolled in spiral form, so that thousands of cut wires occupy only a relatively small space in a cylindrical cartridge. One difficulty with such prior stapling machines is that the driving blade itself and the staple being driven must retract a cam within the forming block.

One of the principal objects of the present invention is to provide a stapling machine of the retractable anvil type having a separate removable roll of cut wires therein. Such a roll might contain 1,000 or more cut wires. Another object is to provide a forming block whose retractable means is retracted by means other than the staple driving blade and the forming staple therebelow. Another object is to provide a stapling machine wherein the first staple which is driven by the driving blade is pre-formed and driven properly without jamming the machine. Another object is to provide a machine in which the first cut wire is stopped at a position under the form ing die, thereby forming said cut wire into a staple at a point prior to the staple driving position.

These and other objects and advantages will become apparent hereinafter.

The present invention is embodied in a stapling machine of the retractable anvil type having a removable roll of staple elements or cut wires, which are formed into staples by a forming die, and are pushed forwardly by pushers which have been retracted by means other than the staple driving blade and the formed staple there below, said staple being directed to a position where the formed staple is directly beneath the driving blade and is ready to be driven and clinched by retractable anvils. The invention is also embodied in the former block and in the means for retracting the retractable element in the former block.

The invention also consists in the parts and in the arrangements and combinations of parts hereinafter de- United States Patent 0 M 3,504,839 Patented Apr. 7, 1970 scribed and claimed. In the accompanying drawings which-form part of this specification and wherein like numerals and symbols refer to like parts wherever they occur:

FIG. 1 is a side elevational view of a hand operated stapling machine embodying the present invention, most of the machine shown in cross-section along a central llfngitudinal line, with a power unit shown in dotted nes,

FIG. 2 is a vertical cross-sectional view taken along the line 22 of FIG. 1,

FIG. 3 is a horizontal cross-sectional view taken along the line 33- of FIG. 1,

FIG. 4 is an enlarged fragmentary front elevational view showing the stapling mechanism, the left half showing the anvil in its fully actuated or lower position and the rght half showing the anvil in its fully retracted or upper postion with the staple leg not yet formed and showing the actuator pins in dotted lines in an intermediate position and a lower position.

FIG. 5 is an exploded perspective view of the forming block embodying the present invention,

FIG. 6 is a top plan view of the assembled forming block, and

FIGS. 7 and 8 are top plan and side elevational views, respectively, of the assembled forming block showing the actuator pins in their upper position, in an intermediate position, and in their lower position.

Referring now to the drawings in detail, it will be seen that the embodiment of the invention which has been illustrated comprises a stapling machine M with a removable roll of staple elements or cut Wires W therein. These cut wires W are connected by means of tape T. The stapling machine M comprises a front housing 1 and a rear housing 2 with a stapling mechanism 3 therebetween. The front housing 1 is provided with a penetration control 4. These parts are similar in construction and operation to the equivalent parts shown in US. Schafroth Patent No. 2,897,502 dated Aug. 4, 1959.

The front housing 1 has a rear face 5. The rear housing 2 has a front face 6. The stapling mechanism 3 is mounted between the housings 1 and 2 and is actuated by an operating lever 7 connected thereto at 8, the forward end of said operating lever 7 being suspended on a pivot pin 9 near the bottom of a link 10 which is free to pivot on a pin 11 secured to a handle casing 12 having a handle 13 with a handhole 14 in its upper portion. The operating lever 7 is connected to a yoke 15 and links 16 having anvil holders 17 at their lower ends for holding retractable anvils 18. The anvil holders 17 each have an actuator pin P connected thereto adjacent to the anvil 18. Springs 16a are connected between the links 16 and pins in the upper portion of the front housing 1. The front housing 1 is provided with a penetration control 4 comprising a cam 19, a follower 20 With a pivot pin 21 therein and a shaft 22 with a wing nut 23 thereon for causing the pivot pin 21 to move up or down to control the penetration depth of the anvils 18. The foregoing parts are similar in construction and operation to those shown and described in the US. Schafroth Patent No. 2,897,502.

The housings 1 and 2 are mounted on a base plate 24 having side edges 25. The base plate 24 supports means for holding a cartridge or roll of cut wires 26. The stapling mechanism 3 includes a staple driving blade 27 in what shall be called position No. 1, with a guide plate 28 and a forming die or punch 29 immediately rearwardly thereof in what shall be called position No. 2. The rear housing 2 is provided with a retainer or means 30 to prevent the cut wires W connected by the tape T from moving rearwardly. The cut wires W are in a roll 26 which is secured within a hinged cover 31 having spring biased closure means 32 thereon. The cut Wires W rest on an upper bottom or ramp 33 as they are unwound from the roll 26, and are guided forwardly by the sides 34 until they extend under the retainer 30 and hold down means 35 mounted on the rear housing 2.

Each cut wire W has a crown or central portion 36 with two end portions 37 which form the legs 37 of a staple S. The edges 38 of each cut wire W are pointed and form the points of the staple S. Each staple S has a bend or curve 39 between the crown 36 and the legs 37. The cut wires W are fastened together by tape T extending over a portion of their crowns 36. A forming block assembly 40, as best shown in FIG. 5, 1s connected to the base plate 24 and positioned between the base plate 24 and the ramp 33. The forming block assembly 40 comprises a support block 41 with a forming plate 42 secured thereto by pins 43 and a screw 44. The forming block assembly 40 has two movable pushers or actuators 45 connected thereto. A rear plate 46 connects the actuators 45 so that both actuators 45 move simultaneously. Screws 46a connect the rear plate 46 to the actuators 45. The rear plate 46 and actuators 45 move as a unit to the rear of the support block 41 and forming plate 43. The actuators 45 are guided in their rearward movement by the forming plate 42, the support block 41, and the wear plate 61. The bolts 47 have forward ends 48 threaded into the support block 41. Resilient means, such as springs 49, circumscribe the bolts 47 and normally keep the rear plate 46 against the rear face of the support block 41. In this position, the front wall 50 of each actuator 45 is flush with the front face 51 of the support block 41. Each actuator 45 has a sloping cam 52 which slopes downwardly and forwardly of the front wall 50 to a line 53 with a vertical front face 54 therebelow. A notch 55 is provided in each inner face 56 of the cam 52 and front wall 50. This notch 55 accommodates any natural spring-back of the cut wire W after it has been formed into a staple S.

The support block 41 may be made of mill steel, but the forming plate 42 should be made of hardened tool steel. A transverse bolt 57 extends through a hole 58 on actuator 45 and a hole 59 in the support block 41 and is threaded into a hole 60 in the opposite actuator 45. The support block hole 59 is larger in diameter than the shank 62 of the transverse bolt 57 so that the actuators 45 may move rearwardly with respect to the support block 41 against the action of the springs 49.

The cut wires W have a slight bow in them with the outer edges 38 being slightly higher than their center 36 due to the manner in which they are manufactured. After the cut wire W is formed by bending its end portions 37 over the forming plate 42 to form the legs 37, the legs 37 do not remain truly parallel to each other due to the inherent springback of the metal used in the cut wire W. Thus, the ends or points 38 do not point vertically downwardly and are slightly divergent. The notches 55 in the inner faces 56 of the cam 52 and vertical front face 54 receive the diverging points and direct them inwardly so that said legs 37 are truly parallel as they are driven into a work surface (not shown) by the staple driving blade 27.

In operation, a roll of cut wires W is inserted in the machine M under the cover 31, as shown in FIG. 1, with the cut wires W extending up the ramp 33 and under the retainer 30 and hold down means 35, until the first cut wire W contacts the auvils 18 in position No. 2 which is directly under the forming die 29.

The lever 7 is then pushed down to preform the first cut wire W into a staple S. The lever 7 is then released, which causes the first staple S to move forward to position No. 1 directly under the staple driving blade 27 and causes the second cut wire W to move forward to position No. 2 directly under the forming die 29.

The driving blade 27 merely contacts the formed staple S and drives it downwardly without having the formed staple S or driving blade 27 or anything directly connected to the driving blade 27 contacting any cam surface. With the present arrangement, the actuator pins P move downwardly and inwardly in an are as the anvil holders 17 are pivoted about the anvil pin 21. During the downward movement, the actuator pins P contact the sloping cam 52 and upon continued downward movement cause the earns 52 and actuators 45 to move rearwardly a distance slightly greater than the width of one cut Wire W. Continued downward movement allows the forming die 29 to bend the end portions 37 of the next cut wire W downwardly over the edges of the forming plate 42 to form a staple S whose legs 37 are positioned in front of the front walls 50. It would be desirable if the legs 37 of the formed sta le S were parallel to each other and perpendicular to the crown 36, but the spring-back of the metal tends to cause said legs 37 to be farther apart at their bottom points 38 than at their upper ends 37 adjacent to the crown 36. The diverging legs 37 are received in the notches 55 which force the legs 37 inwardly so that the legs 37 are in true parallel relation before they contact the work surface.

After the formed staple S has been driven, and the driving blade 27 moved upwardly, the actuator pin P moves upwardly and allows the actuators 36 to move forwardly under the force of the resilient means or springs 40 at the rear of the former block 31, thereby causing the front walls 50 to push the formed staple S forwardly to position No. 1 directly beneath the staple driving blade 27.

In operation, the forward staple S is only partially driven before the actuator pin P contacts the cam 52 to retract the cam 52 so that the second or next adjacent cut wire W can then be formed by bending the cut wire W over the forming plate 42 with the forming dies 29. This occurs as the first staple is being driven. Upon upward movement of the driving blade 27 the actuator pins P are moved upwardly and allow the cams 52 and actuators 45 to move forwardly by reason of the springs 49, at which time the front wall 50 of each actuator 45 moves the legs 37 of the formed staple S forwardly into a position directly beneath the driving blade 27. This moves the entire roll of cut wires W forwardly since the cut wires W remain hingedly connected by the tape T until the driving blade 27 comes down and severs the tape as it drives the formed staple S.

The path of the actuator pin P connected to the anvil holder 17 is shown in FIGS. 4, 7 and 8. Referring to the right portion of FIG. 4, the pin P is shown in solid lines in its upper position, in dotted lines in an intermediate position, and in dotted lines in its lowest position. The actuator pins P are shown in these same three positions in dotted lines in FIGS. 7 and 8. During their arcuate downward movement, the pins P first contact the earns 52 along their outer portions and then move downwardly and inwardly to force the pushers 45 rearwardly until the vertical front face 54 has moved rearwardly the dis tance of one cut wire W and into flush relation with the front face 51 of the support block 41.

The present machine M has the advantage of holding at least 1,000, and up to 5,000, cut wires W which can be easily inserted into the machine when empty. The parts are arranged so that the driving blade 27 cannot drive a cut wire W thereby jamming or damaging the machine, but can only drive a formed staple S. This is accomplished by providing stop means for the cut wires at the forming die, thereby preventing any unformed cut wire from reaching a position under the driving blade 27.

In the present arrangement neither the driving blade 27 nor the staple S nor the forming die 29 contacts the pushers 45 to drive them rearwardly, but instead, means connected to the anvil holders 17 contact the pushers 45 to push them rearwardly independently of the downward movement of the driving blade 27 and forming dies 29.

The present invention is shown in a hand operated machine operated by the operating lever 7 shown in FIG. 1. However, if desired, a power cylinder may replace the lever 7 in the well known manner, as shown in the dotted lines in FIG. 1. This power cylinder must be attached to suitable sources of compressed air.

This invention is intended to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

What is claimed is:

1. In a stapling machine for forming and driving staples formed from a band of cut wires secured together in side by side relation, said stapling machine having a casing with a stapling mechanism therein of the retractable anvil type, said stapling mechanism having a driving blade and a pair of anvils therein, each of said anvils connected to an anvil holder, the improvement which comprises providing a forming block of substantially rectangular shape extending rearwardly of said casing, said forming block having a pusher movably mounted on each side thereof, each of said pushers having a sloping cam thereon at its forward end, said pushers being normally urged forwardly by resilient means so that said cams extend forwardly of the front face of said forming block, said anvil holders each having an actuator pin connected thereto, said actuator pins being adapted to contact said sloping cams to move said pushers rearwardly when said anvil holders are pivoted downwardly to effect the driving of a staple which has previously been formed from the cut wires.

2. The combination set forth in claim 1 wherein said actuator pins are mounted on said anvil holders at a point adjacent to said anvils.

3. The combination set forth in claim 1 wherein staple forming dies are connected to said driving blade above the end portions of said cut wires and contact said end portions to bend said end portions out of the plane of the crown of the staple into a substantially perpendicular position thereto.

4. The combination set forth in claim 1 wherein said actuator pins move downwardly along an arcuate path and inwardly toward each other as said actuator pins slide along the sloping cams and force said sloping cams rearwardly.

5. The combination set forth in claim 1 wherein said driving blade has a staple forming die connected thereto for contacting the end portions of said cut wires and bending said end portions downwardly out of the plane of the crown portion of the staple being formed after the previously formed staple is contacted by the driving blade.

6. The combination set forth in claim 1 wherein said pusher has a sloping cam surface and a lower vertical front surface, the inner edges of which contain a notch therein for receiving the points of the formed staple legs which tend to move outwardly and into said notches because of the spring-back in the metal after the staple legs are formed, said notches bending said staple leg to a vertical position as it is being driven so that it can be driven with legs in a truly vertical direction.

7. The combination set forth in claim 1 wherein the forming block comprises a support block having a separate hardened steel forming plate connected thereto and positioned thereabove.

8. The combination set forth in claim 7 wherein the two movable pushers are connected by a rear plate extending across the rear of said support block, said rear plate being biased toward said support block by springs mounted on bolts secured in said support block and extending through said rear plate.

9. The combination set forth in claim 7 wherein a transverse bolt extends through one pusher and through an opening in said support block larger than said transverse bolt and into the opposite pusher, so that said pushers are connected to each other at their forward and rear portions.

References Cited UNITED STATES PATENTS 1,855,162 4/1932 Zeruneith 227-89 2,156,165 4/1939 Sims 227-89 2,182,594 12/1939 Matveyeff 227l08 2,488,940 11/1949 Schafroth 227-108 2,987,725 6/1961 Heilman 227-108 X 3,013,272 12/1961 Barratt 227 X 3,279,673 10/1966 Schafroth 227108 X 3,404,824 10/1968 Davis 227-140 FOREIGN PATENTS 1,042,384 9/ 1966 Great Britain.

WAYNE A. MORSE, In, Primary Examiner US. Cl. X.R. 227119, 140 

